The border should light up simply and clearly indicating which field the user is currently editing. I am using the following style attribute to set the user input to uppercase so that when the user starts typing in the text box for example railway, then it should be altered to capital letters like RAILWAY without the user having to press the Caps-lock button.. In this post, we will see how to restrict a HTML input text box to allow only numeric values. You can use CSS (Cascading Style Sheets) Style Tags to add a color background to your form input boxes. To create a multi-line text input, use the HTML